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HIU Servicing & Repairs Across Scotland

Servicing, repair and replacement of heat interface units (HIUs) for flats and apartments on communal and district heat networks across Scotland.

Book an HIU service 01355 511105
A heat interface unit with valves, pump and controls installed in an apartment
What is an HIU?

Heat interface units: the heart of a heat-network flat

If your building is heated by a communal or district heat network, you won't have a boiler. Instead, a heat interface unit (HIU) takes heat from the network, delivers it to your radiators and hot water taps, and meters exactly what you use.

Like a boiler, an HIU has valves, a pump, strainers and controls that need regular attention. A well-maintained unit means steadier hot water, lower bills and fewer breakdowns.

See our Dunfermline HIU replacement programme
What's included

A thorough heat interface unit service

1

Inspect & test

We check valves, pumps, seals and controls, and look for leaks, wear and scale.

2

Clean strainers

Blocked strainers are the most common cause of weak heating and lukewarm water, so we clean them out.

3

Optimise settings

We set temperatures and flow rates correctly, so the unit runs efficiently and keeps your bills down.

4

Report back

You get a clear summary of what we found and any work we recommend — no surprises.

An engineer inspecting pipework and plant equipment on a heat network
Repairs & replacements

HIU repairs: no heating or hot water? We can help

From faulty valves and failed pumps to units at the end of their working life, our engineers diagnose HIU faults quickly and explain your options clearly — repair where it makes sense, replace where it doesn't.

  • Fault-finding and repairs when you have no heating or hot water
  • Like-for-like and upgraded HIU replacements
  • Controls, thermostats and heat meter work
  • Experienced in large-scale HIU programmes for housing providers
Good to know

HIU servicing FAQs

How often should my HIU be serviced?

We recommend an annual service, just as you would for a boiler. Some landlords and heat network operators make it a condition of your tenancy or lease, so it's worth checking your agreement.

What are the signs my HIU needs attention?

Hot water that takes a long time to come through or runs lukewarm, radiators that don't get properly hot, unusual noises, leaks or error codes on the unit all suggest it needs a service or repair.

I rent or lease my flat — who is responsible for the HIU?

It depends on your agreement. In many buildings the heat network operator or landlord maintains the unit; in others it's the resident's responsibility. If you're unsure, get in touch and we'll help you find out.

Do you work with landlords and housing associations?

Yes. As well as working with individual homeowners, we deliver HIU servicing, replacement and metering programmes for housing providers and heat network operators. See our commercial services.